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From Krishna Kishore Bonagiri <write2kish...@gmail.com>
Subject Re: Question about Block size configuration
Date Tue, 12 May 2015 05:47:00 GMT
The default HDFS block size 64 MB means, it is the maximum size of block of
data written on HDFS. So, if you write 4 MB files, they will still be
occupying only 1 block of 4 MB size, not more than that. If your file is
more than 64MB, it gets split into multiple blocks.

If you set the HDFS block size to 2MB, then your 4 MB file will get split
into two blocks.

On Tue, May 12, 2015 at 8:38 AM, Himawan Mahardianto <mahardianto@ugm.ac.id>

> Hi guys, I have a couple question about HDFS block size:
> What if I set my HDFS block size from default 64 MB to 2 MB each block,
> what will gonna happen?
> I decrease the value of a block size because I want to store an image file
> (jpeg, png etc) that have size about 4MB each file, what is your opinion or
> suggestion?
> What will gonna happen if i don't change the default size of a block size,
> then I store an image file with 4MB size, will Hadoop use full 64MB block,
> or it will create 4Mb block instead 64MB?
> How much memory used on RAM to store each block if my block size is 64MB,
> or my block size is 4MB?
> Is there anyone have experience with this? Any suggestion are welcome
> Thank you

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